Preparation and characterisation of tri-calcium phosphate scaffolds with tunnel-like macro-pores for bone tissue engineering

Calcium Phosphate ceramics have been widely used in tissue engineering due to their excellent biocompatibility and biodegradability. In the physiological environment, they are able to gradually degrade, absorbed and promote bone growth. Ultimately, they are capable of replacing damaged bone with new tissue. However, their low mechanical properties limit calcium phosphate ceramics in load-bearing applications. To obtain sufficient mechanical properties as well as high biocompatibility is one of the main focuses in biomaterials research. Therefore, the current project focuses on the preparation and characterization of porous tri-calcium phosphate (TCP) ceramic scaffolds. Hydroxapatite (HA) was used as the raw material, and normal calcium phosphate bioglass was added to adjust the ratio between calcium and phosphate. It was found that when 20% bioglass was added to HA and sintered at 1400oC for 3 hours, the TCP scaffold was obtained and this was confirmed by X-ray diffraction (XRD) analysis. Test results have shown that by applying this method, TCP scaffolds have significantly higher compressive strength (9.98MPa) than those made via TCP powder (<3MPa). Moreover, in order to further increase the compressive strength of TCP scaffolds, the samples were then coated with bioglass. For normal bioglass coated TCP scaffold, compressive strength was 16.69±0.5MPa; the compressive strength for single layer mesoporous bioglass coated scaffolds was 15.03±0.63MPa. In addition, this project has also concentrated on sizes and shapes effects; it was found that the cylinder scaffolds have more mechanical property than the club ones. In addition, this project performed cell culture within scaffold to assess biocompatibility. The cells were well distributed in the scaffold, and the cytotoxicity test was performed by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay. The Alkaline Phosphatase (Alp) activity of human bone marrow mesenchymal stem cell system (hBMSCs) seeded on scaffold expressed higher in vitro than that in the positive control groups in osteogenic medium, which indicated that the scaffolds were both osteoconductive and osteoinductive, showing potential value in bone tissue engineering.

An architecture for enhanced assurance in e-health systems

Notwithstanding the obvious potential advantages of information and communications technology (ICT) in the enhanced provision of healthcare services, there are some concerns associated with integration of and access to electronic health records. A security violation in health records, such as an unauthorised disclosure or unauthorised alteration of an individual's health information, can significantly undermine both healthcare providers' and consumers' confidence and trust in e-health systems. A crisis in confidence in any national level e-health system could seriously degrade the realisation of the system's potential benefits. In response to the privacy and security requirements for the protection of health information, this research project investigated national and international e-health development activities to identify the necessary requirements for the creation of a trusted health information system architecture consistent with legislative and regulatory requirements and relevant health informatics standards. The research examined the appropriateness and sustainability of the current approaches for the protection of health information. It then proposed an architecture to facilitate the viable and sustainable enforcement of privacy and security in health information systems under the project title "Open and Trusted Health Information Systems (OTHIS)". OTHIS addresses necessary security controls to protect sensitive health information when such data is at rest, during processing and in transit with three separate and achievable security function-based concepts and modules: a) Health Informatics Application Security (HIAS); b) Health Informatics Access Control (HIAC); and c) Health Informatics Network Security (HINS). The outcome of this research is a roadmap for a viable and sustainable architecture for providing robust protection and security of health information including elucidations of three achievable security control subsystem requirements within the proposed architecture. The successful completion of two proof-of-concept prototypes demonstrated the comprehensibility, feasibility and practicality of the HIAC and HIAS models for the development and assessment of trusted health systems. Meanwhile, the OTHIS architecture has provided guidance for technical and security design appropriate to the development and implementation of trusted health information systems whilst simultaneously offering guidance for ongoing research projects. The socio-economic implications of this research can be summarised in the fact that this research embraces the need for low cost security strategies against economic realities by using open-source technologies for overall test implementation. This allows the proposed architecture to be publicly accessible, providing a platform for interoperability to meet real-world application security demands. On the whole, the OTHIS architecture sets a high level of security standard for the establishment and maintenance of both current and future health information systems. This thereby increases healthcare providers‘ and consumers‘ trust in the adoption of electronic health records to realise the associated benefits.

Reliability of ultrasonographic measurement of the architecture of the vastus lateralis and gastrocnemius medialis muscles in older adults

Objective To determine the test-retest reliability of measurements of thickness, fascicle length (Lf) and pennation angle (θ) of the vastus lateralis (VL) and gastrocnemius medialis (GM) muscles in older adults. Participants Twenty-one healthy older adults (11 men and ten women; average age 68·1 ± 5·2 years) participated in this study. Methods Ultrasound images (probe frequency 10 MHz) of the VL at two sites (VL site 1 and 2) were obtained with participants seated with knee at 90º flexion. For GM measures, participants lay prone with ankle fixed at 15º dorsiflexion. Measures were taken on two separate occasions, 7 days apart (T1 and T2). Results The ICCs (95% CI) were: VL site 1 thickness = 0·96(0·90–0·98); VL site 2 thickness = 0·96(0·90–0·98), VL θ = 0·87(0·68–0·95), VL Lf = 0·80(0·50–0·92), GM thickness = 0·97(0·92–0·99), GM θ = 0·85(0·62–0·94) and GM Lf =0·90(0·75–0·96). The 95% ratio limits of agreement (LOAs) for all measures, calculated by multiplying the standard deviation of the ratio of the results between T1 and T2 by 1·96, ranged from 10·59 to 38·01%. Conclusion The ability of these tests to determine a real change in VL and GM muscle architecture is good on a group level but problematic on an individual level as the relatively large 95% ratio LOAs in the current study may encompass the changes in architecture observed in other training studies. Therefore, the current findings suggest that B-mode ultrasonography can be used with confidence by researchers when investigating changes in muscle architecture in groups of older adults, but its use is limited in showing changes in individuals over time.

Hypoxia-mimicking mesoporous bioactive glass scaffolds with controllable cobalt ion release for bone tissue engineering

Low oxygen pressure (hypoxia) plays an important role in stimulating angiogenesis; there are, however, few studies to prepare hypoxia-mimicking tissue engineering scaffolds. Mesoporous bioactive glass (MBG) has been developed as scaffolds with excellent osteogenic properties for bone regeneration. Ionic cobalt (Co) is established as a chemical inducer of hypoxia-inducible factor (HIF)-1α, which induces hypoxia-like response. The aim of this study was to develop hypoxia-mimicking MBG scaffolds by incorporating ionic Co2+ into MBG scaffolds and investigate if the addition of Co2+ ions would induce a cellular hypoxic response in such a tissue engineering scaffold system. The composition, microstructure and mesopore properties (specific surface area, nano-pore volume and nano-pore distribution) of Co-containing MBG (Co-MBG) scaffolds were characterized and the cellular effects of Co on the proliferation, differentiation, vascular endothelial growth factor (VEGF) secretion, HIF-1α expression and bone-related gene expression of human bone marrow stromal cells (BMSCs) in MBG scaffolds were systematically investigated. The results showed that low amounts of Co (< 5%) incorporated into MBG scaffolds had no significant cytotoxicity and that their incorporation significantly enhanced VEGF protein secretion, HIF-1α expression, and bone-related gene expression in BMSCs, and also that the Co-MBG scaffolds support BMSC attachment and proliferation. The scaffolds maintain a well-ordered mesopore channel structure and high specific surface area and have the capacity to efficiently deliver antibiotics drugs; in fact, the sustained released of ampicillin by Co-MBG scaffolds gives them excellent anti-bacterial properties. Our results indicate that incorporating cobalt ions into MBG scaffolds is a viable option for preparing hypoxia-mimicking tissue engineering scaffolds and significantly enhanced hypoxia function. The hypoxia-mimicking MBG scaffolds have great potential for bone tissue engineering applications by combining enhanced angiogenesis with already existing osteogenic properties.

Enterprise architecture and the integration of service-oriented architecture

In recent years, enterprise architecture (EA) has captured a growing attention as a means to systematically consolidate and interrelate diverse business and IT artefacts in order to provide holistic decision support. The recent popularity of a service-orientation has added “service “and related constructs as a new element that requires consideration within an Enterprise Architecture. Since the emergence of the Service-Oriented Architecture (SOA), many attempts have been made to incorporate SOA artefacts in existing EA frameworks. Yet, the approaches taken to achieve this goal differ substantially for the most commonly used EA frameworks to date. SOA in the context of enterprise architecture is one of the future research challenges. Several authors argue that further research is needed in order to understand how SOA impacts prior enterprise architecture frameworks. This study explores SOA integration within EA, identifies SOA integration approaches within EA and identifies factors that impact SOA integration within Enterprise Architecture.

A natural model for architecture

In John Frazer's seminal book An Evolutionary Architecture (1995), from which this essay is extracted, a fundamental approach is established for have natural systems can unfold mechanisms for negotiating the complex design space inherent in architectural systems. In this essay, which forms a critical part of the book, Frazer draws both correlations and distinctions from natural processes as emulated in design processes and form as active manifestations within natural systems. Form is seen as an evolving agent generated via the rules of descriptive genetic coding, functioning as a part of a metabolic environment. Frazer's process-model establishes the realm in which computation must manoeuvre to produce a valid solution space, including the operations of self-organisation, complexity and emergent behaviour. Addressing design as an authored practice, he extends the transference of 'creativity' from the explicit impression into form, to the investment of though, organisation and strategy in the computational processes which produce form. Frazer's text concentrates astutely on the practising of the evolutionary paradigm, the output of which postulates an architecture born of the relationships to dynamic environmental and socio-economic contexts, and realised through morphogenetic materialisation.

Building information modeling in the Australian architecture engineering and construction industry

Building Information Modeling (BIM) is a modern approach to the design, documentation, delivery, and life cycle management of buildings through the use of project information databases coupled with object-based parametric modeling. BIM has the potential to revolutionize the Architecture, Engineering and Construction (AEC) industry in terms of the positive impact it may have on information flows, working relationships between project participants from different disciplines and the resulting benefits it may achieve through improvements to conventional methods. This chapter reviews the development of BIM, the extent to which BIM has been implemented in Australia, and the factors which have affected the up-take of BIM. More specifically, the objectives of this chapter are to investigate the adoption of BIM in the Australian AEC industry and factors that contribute towards the uptake (or non uptake) of BIM. These objectives are met by a review of the related literature in the first instance, followed by the presentation of the results of a 2007 postal questionnaire survey and telephone interviews of a random sample of professionals in the Australian AEC industry. The responses suggest that less than 25 percent of the sample had been involved in BIM – rather less than might be expected from reading the literature. Also, of those who have been involved with BIM, there has been very little interdisciplinary collaboration. The main barriers impeding the implementation of BIM widely across the Australian AEC industry are also identified. These were found to be primarily a lack of BIM expertise, lack of awareness and resistance to change. The benefits experienced as a result of using BIM are also discussed. These include improved design consistency, better coordination, cost savings, higher quality work, greater productivity and increased speed of delivery. In terms of conclusion, some suggestions are made concerning the underlying practical reasons for the slow up-take of BIM and the successes for those early adopters. Prospects for future improvement are discussed and proposals are also made for a large scale worldwide comparative study covering industry-wide participants

Study of tissue damage during mechanical peeling of tough skinned vegetables

Peeling is an essential phase of post harvesting and processing industry; however the undesirable losses and waste rate that occur during peeling stage are always the main concern of food processing sector. There are three methods of peeling fruits and vegetables including mechanical, chemical and thermal, depending on the class and type of fruit. By comparison, the mechanical method is the most preferred; this method keeps edible portions of produce fresh and creates less damage. Obviously reducing material losses and increasing the quality of the process has a direct effect on the whole efficiency of food processing industry which needs more study on technological aspects of this industrial segment. In order to enhance the effectiveness of food industrial practices it is essential to have a clear understanding of material properties and behaviour of tissues under industrial processes. This paper presents the scheme of research that seeks to examine tissue damage of tough skinned vegetables under mechanical peeling process by developing a novel FE model of the process using explicit dynamic finite element analysis approach. In the proposed study a nonlinear model which will be capable of simulating the peeling process specifically, will be developed. It is expected that unavailable information such as cutting force, maximum shearing force, shear strength, tensile strength and rupture stress will be quantified using the new FEA model. The outcomes will be used to optimize and improve the current mechanical peeling methods of this class of vegetables and thereby enhance the overall effectiveness of processing operations. Presented paper aims to review available literature and previous works have been done in this area of research and identify current gap in modelling and simulation of food processes.

Tissue engineering bone - reconstruction of critical sized segmental bone defects in a large animal model

Currently, well established clinical therapeutic approaches for bone reconstruction are restricted to the transplantation of autografts and allografts, and the implantation of metal devices or ceramic-based implants to assist bone regeneration. Bone grafts possess osteoconductive and osteoinductive properties, their application, however, is associated with disadvantages. These include limited access and availability, donor site morbidity and haemorrhage, increased risk of infection, and insufficient transplant integration. As a result, recent research focuses on the development of complementary therapeutic concepts. The field of tissue engineering has emerged as an important alternative approach to bone regeneration. Tissue engineering unites aspects of cellular biology, biomechanical engineering, biomaterial sciences and trauma and orthopaedic surgery. To obtain approval by regulatory bodies for these novel therapeutic concepts the level of therapeutic benefit must be demonstrated rigorously in well characterized, clinically relevant animal models. Therefore, in this PhD project, a reproducible and clinically relevant, ovine, critically sized, high load bearing, tibial defect model was established and characterized as a prerequisite to assess the regenerative potential of a novel treatment concept in vivo involving a medical grade polycaprolactone and tricalciumphosphate based composite scaffold and recombinant human bone morphogenetic proteins.

Endogenous musculoskeletal tissue engineering : a focussed perspective

Two major difficulties facing widespread clinical implementation of existing Tissue Engineering (TE) strategies for the treatment of musculoskeletal disorders are (1) the cost, space and time required for ex vivo culture of a patient’s autologous cells prior to re-implantation as part of a TE construct, and (2) the potential risks and availability constraints associated with transplanting exogenous (foreign) cells. These hurdles have led to recent interest in endogenous TE strategies, in which the regenerative potential of a patient’s own cells is harnessed to promote tissue regrowth without ex vivo cell culture. This article provides a focused perspective on key issues in the development of endogenous TE strategies, progress to date, and suggested future research directions toward endogenous repair and regeneration of musculoskeletal tissues and organs.

Place and displacement : southeast Queensland architecture

The "vernacular" housing tradition of southeast Queensland is easily identifiable. Its history is more complex. This study seeks to challenge two popular conceptions of the "Queenslander" history by showing that they actually provide contradictory explanations. The aim is to produce a more complex account of local architecture and its historical explanation so that both its past and its present practices can be better understood as a distinctly subtropical idiom. This discussion shows that such practices may respond to common concerns but that are also ever-changing.

Entertainment architecture : constructing a framework for the creation of an emerging transmedia form

This thesis investigates the radically uncertain formal, business, and industrial environment of current entertainment creators. It researches how a novel communication technology, the Internet, leads to novel entertainment forms, how these lead to novel kinds of businesses that lead to novel industries; and in what way established entertainment forms, businesses, and industries are part of that process. This last aspect is addressed by focusing on one exemplary es-tablished form: movies. Using a transdisciplinary approach and a combination of historical analysis, industry interviews, and an innovative mode of ‘immersive’ textual analysis, a coherent and comprehensive conceptual framework for the creation of and re-search into a specific emerging entertainment form is proposed. That form, products based on it, and the conceptual framework describing it are all re-ferred to as Entertainment Architecture (‘entarch,’ for short). The thesis charac-terises this novel form as Internet-native transmedia entertainment, meaning it fully utilises the unique communicative characteristics of the Internet, and is spread across media. The thesis isolates four constitutive elements within Entertainment Architec-ture: story, play, ‘dance,’ and ‘glue.’ That is, entarch tells a story; offers playful interaction; invites social interaction between producer and consumer, and amongst consumers (‘dance’); and all components of it can be spread across many media, but are so well interconnected and mutually dependent that they are perceived as one product instead of many (‘glue’). This sets entarch apart from current media franchises like Star Wars or Halo, which are perceived as many products spread across many media. Entarch thus embraces the commu-nicative behaviour of Internet-native consumers instead of forcing them to de-sist from it, it harnesses the strengths of various media while avoiding some of their weaknesses, and it can sustain viable businesses. The entarch framework is an innovative contribution to scholarship that al-lows researchers to investigate this emerging entertainment form in a structured way. The thesis demonstrates this by using it to survey business models appro-priate to the entarch environment. The framework can also be used by enter-tainment creators — exemplified in the thesis by moviemakers — to delimit the room for manoeuvre available to them in a changing environment.